Problems with ICDs made by Guidant have made headlines in recent months, and next month the Heart Rhythm Society is convening a daylong meeting on ICD safety. The pair of commentaries in the Aug. 24 issue of the Journal of the American Medical Association provided a preview of that meeting.

William H. Maisel M.D., M.P.H., of Brigham and Women's Hospital here wrote that changes are needed in the FDA's Medical Device Malfunction Notification process, beginning with the need to inform the patient who has a defective implant. Dr. Maisel chairs the FDA's Circulatory System Medical Devices Advisory Panel, and he is a member of the Health Policy Committee at the Heart Rhythm Society.

Currently, when a device is recalled the manufacturer notifies the physician but does not notify the patient, Dr. Maisel wrote. By contrast when an automobile recall takes place, the car's owner -- not the dealer who sold the car -- is notified.

Patients are "knowledgeable, informed and proactive, and they have the right to know about malfunctions or potential defects affecting their implantable device," he wrote. Dr. Maisel said that physicians should be notified, perhaps even before the patient is notified, but direct patient notification is a long overdue fix.

Moreover, when a manufacturer learns of a device malfunction, the maker should be required to publicly report the malfunction. Currently the manufacturers are required to tell the FDA about any malfunction that "causes or could cause significant injury," but there is no hard and fast requirement to inform either physicians or the general public.

In the second commentary, a team of cardiologists at Mount Sinai in New York wrote that current guidelines for use of an ICD as primary prevention of sudden cardiac death fail to identify a large number of patients who die from sudden cardiac death -- the very patients who could benefit from a life-saving shock.

Anil Gehi, M.D., and colleagues wrote that the problem is that risk stratification relies solely on ejection fraction. An EF of less than 35% is the threshold.

They cautioned that while ejection fraction is a good prognostic marker for sudden cardiac death, "it may not be a reproducible measurement. The echocardiographic measurement of left ventricular dimensions can vary significantly in weekly repeated measurements in an individual patient. The limits of agreement may vary by as much as 8.5% above or below the mean calculated EF in repeated studies."

A better approach, they wrote, would be to develop a registry of patients with cardiac disease that would include EF as well as signal-averaged electrocardiogram, heart-rate variability, baroreflex sensitivity, heart rate profile during and after exercise, maximum oxygen consumption during exercise, microvolt T-wave alternans, and serum BNP level. Patients with or without ICDs could be entered on the registry and outcome data accumulated over time.

It would then "be possible to develop a risk score to more accurately predict sudden-cardiac death." Such a risk score, the authors concluded, might even allow clinicians to identify high-risk patients who survive myocardial infarction with a well-preserved EF, "thus making inroads into the large population of at-risk patients who would not otherwise qualify for an ICD by current guidelines."

Reviewed by Robert Jasmer, MD Assistant Professor of Medicine, University of California, San Francisco